A passive entry passive start system allows a driver, or anyone who possesses an authorized key fob, to unlock a vehicle's doors as they approach the vehicle without touching a key fob. Once the key fob is within range of the vehicle e.g., 1 m) locked doors can be open by pulling a door handle. In addition, some PEPS systems can be configured to automatically start the vehicle's engine as an authorized key fob approaches the vehicle. Other PEPS systems require that the driver pushes an ignition button to start and/or stop the vehicle engine.
PEPS systems typically require multiple low frequency (LF) (e.g., 125 kHz) transmitting antennas both inside and outside the vehicle. External antennas can be located in the door handles. In one PEPS system, the key fob detects the low-power signal emitted from the vehicle, and automatically responds by emitting a key code or other identifier. A receiver in the vehicle receives the key code (or other identifier) and sends it to an electronic control unit (ECU). If the key code (or other identifier) is confirmed, the key fob is “authorized,” and the ECU unlocks the doors when the driver touches or pulls on a door handle. To start the vehicle engine, the driver simply pushes an ignition button. The ECU allows the engine to start only when the key fob is detected within the cabin of the vehicle and the key code is confirmed again.
Integration of these antennas and other hardware and wiring needed to implement a PEPS system is costly, and it is always desirable to reduce the cost of vehicles that include such PEPS systems.
A typical PEPS system employs a key fob that communicates with a central module located in the vehicle. However, in some cases, the key fob is unavailable or does not work. For example, the driver can lose their key fob, or inadvertently lock it in their vehicle. In addition, the key fob authorization process requires that the key fob is operable and can communicate with the vehicle. In such cases, it would be desirable to provide a backup method of unlocking and starting the vehicle. Stated differently, it would be desirable to provide alternatives to always having to use a key fob in a PEPS system.
The security of communications between a key fob and a vehicle is relatively strong. The key fob is programmed with a unique key when it is manufactured, and is then paired with the vehicle either during manufacturing or at the dealership. The programming is done out of band using a special programming device that outsiders do not have access to. In addition, the key fob has its own unique Bluetooth address that does not change. Further, the key fob does not run software that allows it to communicate with other devices (aside from the programming device and the vehicle).
However, when a wireless communication device, such as a smart phone, is used in place of the key fob as part of a PEPS system, additional security risks arise that would not be a concern when the key fob is used. A unique key stored at the wireless communication device could be accessed using a number of different hacking techniques. Once someone has access to the unique key, they can use it to communicate with the vehicle as if they were authorized to do so. This could allow someone to gain access to the vehicle.
In addition, some alternative PEPS systems are insecure and susceptible to relay station attacks. In some cases, the vehicle can be unlocked and/or started without the driver intending to allow the same. As such, it would be desirable to provide more secure PEPS systems that employ more sophisticated security mechanisms.
Accordingly, it is desirable to improved PEPS systems that can help resolve one or more of the drawbacks mentioned above. For instance, it would be desirable to provide a PEPS system that provides improved security with respect to communications between a vehicle and a wireless communication device, such as a smart phone. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.